JPH0623035Y2 - Circuit board module with latch mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a circuit board module having a latch mechanism,
In particular, it relates to improvement of a latch mechanism for fixing a circuit board module to a mounting rack.

[Prior Art] Complex and large electrical networks, such as Systems control networks for ships and reactors, are typically multiple small circuits each mounted on a modular circuit board (circuit board module). Is decomposed into. These circuit boards, which are electrically interconnected to form a network, allow for quick and easy replacement of defective circuit components and provide greater design flexibility.

The circuit board is typically rectangular and is mounted vertically on the rack. Generally, the top and bottom edges of the circuit board slide in the rack and have electrical connector means with a trailing edge.

The front side of the circuit board module is equipped with plates for handling, identification and aesthetic purposes. Also, some mechanism is typically provided to secure the circuit board module to the circuit board rack. This prevents the circuit board module from disengaging, so that some disengagement force is caused by accidents such as earthquakes, vibrations, sudden ship rocking movements or contact of the caretaker's mop handle end. It is intended to prevent damage to the network when added to the board module. The present invention relates to such a latch mechanism.

SUMMARY OF THE INVENTION One known prior art latch mechanism is of the screw type. Machined screws pass through the plate on the front of the circuit board module and screw into the screw holes in the rack. The drawbacks of the screw type are the need to manufacture, store and assemble costly machined parts and the use of separate tools to ensure a secure, lasting engagement. .

Another known prior art latching mechanism is of the plunger type in which the plunger is slidably disposed in an expansible sleeve mounted on the faceplate. When the circuit board module is inserted into the rack, the sleeve penetrates the hole provided for it. When the plunger is pushed into the sleeve in this condition, the sleeve expands to a size larger than that of the hole, thereby providing a latch that prevents the sleeve from slipping out of the hole.
The disadvantage of the plunger type is that it is expensive to store and assemble, and currently the source (manufacturer) of this particular device is
It is only possible that the circuit board module may not be actually latched when fully inserted into the working position of the rack.

SUMMARY OF THE INVENTION The present invention provides a latching mechanism integral with the front plate to eliminate the separate parts, and simply insert the circuit board module sufficiently to ensure a secure and permanent engagement. This guarantee eliminates the drawbacks of the prior art latch mechanism. It does not require any tool or any action other than just inserting. Moreover, the dimensions of this one-piece latch mechanism can be directly replaced with a plate-type mechanism.

The one-piece latch mechanism includes a bayonet member (prong) having a tapered pointed tapered head and a shaft terminating at the head. The insert is resiliently attached to the front plate of the circuit board module and aligned with the holes in the circuit board module rack. When the circuit board module is inserted into the rack, the tapered surface near the tip of the insert member head engages the edge of the hole. Further insertion of the circuit board module forces the resilient mounting means to deflect so that the tapered surface abuts the edge of the hole.

When the head is fully inserted into the hole, the elastic mounting means return the plug-in member to its original position, thus locking the head at the rear of the mounting plate. The circuit board module positions the plug member head in alignment with the hole and allows the circuit board module, and thus the head of the integrated latch plug member, to be unlocked by pulling it out of the hole in the mounting plate. it can.

An object of the present invention is to provide a circuit board module having a latch mechanism integrated with the front plate of the circuit board module.

Another object of the present invention is to provide a latching mechanism that has the advantages described above and eliminates the need to use multiple parts.

Another object of the present invention is to provide a latching mechanism that has the advantages described above and does not require tools to perform the latching.

Another object of the present invention is to provide a latching mechanism which has the above mentioned advantages and which automatically ensures positive latching engagement simply by inserting the circuit board module into its rack.

Other objects and advantages of the present invention will be readily apparent from the following description with reference to the accompanying drawings which illustrate preferred embodiments of the present invention.

Embodiment Referring now to FIG. 1, a plurality of circuit board modules incorporating a preferred embodiment of a latch mechanism according to the present invention are generally indicated by reference numeral 10. These circuit board modules 10 are shown in place on a circuit board module rack 14. Rack 14 may be of any suitable configuration that provides the following essential features. (1) Alignment of circuit board modules, which are upper and lower tracks 16 and 17
Are each illustrated by. (2) Support for the circuit board module, which is illustrated by the support beam 15 extending between the module mount 26 and the rack rear wall 13. (3) Electrical connection plugs 18 (only one shown) enable interconnection of circuit board modules.

The module front plate 12 is molded from a polycarbonate raw resin. NO.940 Clear Lexan (LE
XAN, trade name of General Electric Company, USA) is used in the preferred embodiment. This material provides sufficient strength as a support and sufficient resilience for the operation of the latch as described in detail below.
The resin may be colored or colored if desired for aesthetic effects.

Latch holes 24 in mount 26 are shown in FIG.
Holes 24 are provided in each circuit board module 10.

Referring to FIG. 2, a side view of the circuit board module 10 of FIG. 1 is shown. The circuit board 11 is fixed to the plate 12 by screws 33. The electrical connector 19 provides an electrical interface to the plug 18. The front plate 12 includes the latch (arm) tabs 21 and inserts 22 of the latch block 20 and other components, all molded in one piece by LEXAN. The front plate 12 will be described in detail later.

Referring to FIG. 3, a prior art screw type latching mechanism is illustrated. A machined screw 32 is attached by a C-shaped clip 34 to the front plate 30 of the circuit board module.
Is held in the screw hole 3 of the module mount 27.
Screw with 1. Bearing washers 36 are provided to prevent damage to the plate 30. As noted above, the drawbacks of this mechanism are the need to manufacture, store and assemble expensive machined parts, and separate tools, such as screwdrivers and allen to ensure a secure, lasting engagement. -It is necessary to use a wrench.

Figures 4, 5 and 6 show a prior art plunger type latch mechanism. FIG. 4 shows the position of the module front plate 40 before the circuit board module is fully inserted into the circuit board module rack. An extension member 46 extends through the circuit board module front plate 40 and is aligned with the holes 24 in the module mount 26. In FIG. 5, the circuit board module has been fully inserted and the extension member 46 has holes 24.
In place, but no latching is done. In FIG. 6, the plunger 41 is inserted, thereby expanding the extension member 46 to a size larger than the hole 24 and latching. As noted above, the drawbacks of the plunger type latch mechanism are the cost of storage and assembly, the single source of this particular device, and the circuit board in the rack's operative position without actual latching. The module can be fully inserted and therefore accidental disengagement can occur.

Referring to FIG. 7, there is shown a preferred embodiment of the integrated latch mechanism according to the present invention. Circuit board module 1
The circuit board 11 attached to the zero module front plate 12 is shown in a position not fully inserted into the rack 14. The latch block 20 is integral with the lower portion of the front plate 12 and protrudes from this lower portion,
It serves to provide a finger grip for withdrawing the module 10 from the rack 14. The latch tabs 21 extend from the latch block 20 toward the rear of the rack 14 toward the module mounts 26 of the rack. An insert (prong) 22 extends from the latch tab 21 towards the rear of the rack as well. The plug member 22 includes a shaft portion 25 extending between the tab 21 and the plug member shoulder 34 and a tapered head 28 between the shoulder 34 and tip 23.

Referring to FIG. 8, when the module 10 is inserted, the insertion head 22 of the insertion member 22 contacts the lower edge of the hole 24 of the module mount 26.
Are aligned with module 10 on tracks 16 and 17. Shoulder 34 is diametrically smaller than hole 24, allowing insert 22 to pass through hole 24.

With reference to FIG. 9, when the module 10 is fully inserted into the rack 14 so that the connector 19 engages the plug 18, the shoulder 34 is completely past the hole 24 and the shaft 25 is in the hole 24. As noted above, in the preferred embodiment, the faceplate material is such that the edges of the holes 24 are required to elastically bend when the edges of the holes 24 abut the tapered head 28, and the shoulders 34 provide holes 24. The tabs 21 are selected to provide the elasticity necessary to elastically return to their original position when passed. When the tab 21 returns to its original position, the shoulder 34 interfacing with the module mount 26 prevents the module 10 from being removed from the rack 14 and is thus latched.

Referring to FIG. 10, there is shown a perspective view of the front plate 12 of the module 10 with the circuit board 11 removed. The front plate 12 is a one-piece molded product and includes all the parts shown in FIG. Front wall 49 of front plate 12
Are oriented at right angles to the sidewalls 48. The circuit board 11 (see FIG. 2) is attached to the side wall 48 at the same height by screws 33 and screw holes 35. The upper gusset 52 and the lower gusset 53 serve as a support that maintains the right angle relationship between the front wall 49 and the side wall 48. The latch block 20 extends from the lower portion 51 of the front wall 49 to the front of the front wall at the lower gusset 53 and its lower portion. The latch tab 21 extends rearward from the front lower edge of the latch block 20 on the lower side and terminates in a tab lip 39.
The insertion member 22 extends rearward from the tab lip 39 below the gusset 53.

Referring to FIG. 11, a rear view of the insert 22 is shown. In this view, the latching mechanism is in the latched position so that the plug-in member 22 extends through the hole 24 and engages the mount 26. The tab lip 39 and the lower lip 38 of the latch tab 21 are shown in phantom.

FIG. 12 illustrates in more detail the more salient features of the latching mechanism of the preferred embodiment. Latch block 20
Is hollow and provided with gussets 29 for strength to reinforce the latch block 20. Upper lip 37 and lower lip 38, along with grip tread 36, provide finger and thumb gripping means for pushing latch tab 21 toward latch block 20 to extract module 10 from rack 14.

The above description and drawings are merely illustrative of one embodiment that achieves the objects, features and advantages of the present invention, and is not intended to limit the present invention thereto. Any modification or change of the present invention within the spirit and scope of the utility model registration claim shall be considered as a part of the present invention.

Effect of the Invention According to the configuration of the present invention described above, no costly machined parts are required, no parts need to be assembled, any action other than simply inserting the circuit board module into a rack, and a tool. There are many significant advantages, such as the need for a simple, fully inserted circuit board module into a rack to automatically maintain a secure, permanent lock. Further, there is an advantage that it can be formed in a size that can be directly replaced with the conventional plunger type latch mechanism.

[Brief description of drawings]

1 is a perspective view of a circuit board module having a latch mechanism according to a preferred embodiment of the present invention, which is located at a proper position in a circuit board module rack, FIG. 2 is a right side view of the module of FIG. 1, and FIG. FIG. 4 is a schematic cross-sectional view of a prior art screw-type latch mechanism for a circuit board module, FIG. 4 is a schematic cross-sectional view of a conventional plunger-type latch mechanism for a circuit board module, and FIG. 5 is a position where the module is fully inserted. Fig. 6 is a schematic cross-sectional view similar to Fig. 4 showing a state where the plunger type latch mechanism is not engaged, and Fig. 6 is a schematic cross-sectional view similar to Fig. 5 showing a state where the plunger type latch mechanism is engaged. FIG. 7 is a side view showing a partial cross section of an integral latch mechanism for a circuit board module according to a preferred embodiment of the present invention, and FIG. 8 shows a state in which the latch mechanism is partially engaged. 7 is a side view similar to FIG. 7, FIG. 9 is a side view similar to FIG. 7 showing the latch mechanism fully engaged, and FIG. 10 is the front of the module incorporating the latch mechanism of the preferred embodiment of the present invention. FIG. 11 is a perspective view of the plate, FIG. 11 is a sectional view of FIG. 9 taken along line XI-XI, and FIG. 12 is a detailed perspective view of the latch mechanism of the preferred embodiment of the present invention. 10: Circuit board module 11: Circuit board 12: Front plate 14: Circuit board module rack 18: Electrical connection plug 19: Electrical connector 20: Latch block 21: Latch tab 22: Insert member 24: Latch hole 25: Insert member Shaft portion 26: Module mount 28: Insert member tapered head 34: Insert member shoulder 48: Side wall 49: Front plate front wall 52: Upper gusset 53: Lower gusset

Claims (4)

[Scope of utility model registration request] 1. A circuit board module (10) provided with a latch mechanism and slidably arranged in a mounting rack (14) having a latch hole (24), wherein the circuit board (11) is mounted on the module. In a circuit board module having a generally rectangular face plate (12) oriented substantially at a right angle to the front plate, the latch mechanism integrally formed with the face plate by a single material is substantially hollow in the lateral direction. And a latch block (20) extending from the lower part of the front plate to the front, and from the lower front edge of the latch block to the rear part apart from the lower part of the latch block and to the upper part. A resilient latch tab (21) that is deflectable, a plug that has a head (28) and a shaft portion (25), and is aligned to engage the latch hole (24) of the mounting rack. The member (22), A foot portion extends rearwardly from the latch tab and the head has a shoulder (34) located at an end of the shaft portion and extending below the shaft portion and rearwardly from the shoulder portion. tip
(23) is formed in a taper shape, the shoulder portion of the head comprises an insertion member (22) for engaging with the latch hole of the mounting rack, Circuit board module equipped. 2. The utility model registration claim 1 wherein a plurality of treads (36) are formed on the upper surface of the latch block and a plurality of treads (36) are formed on the lower surface of the latch tab. Circuit board module with a latch mechanism. 3. An upper lip (3) on the upper surface of the latch block.
7) is formed, and the lower lip (38) is formed on the lower surface of the latch tab. The circuit board module provided with the latch mechanism according to claim 1 or 2 of the utility model registration claim. 4. A circuit board module having a latch mechanism according to claim 1, wherein the single material is a polycarbonate resin.